Yes alk. batteries are only about 65% at 32F and nearly nothing when temps are less than 0F. However lithiums still retain 90% at 32F and 50% at 0F. Just one problem with them is, do not store them in warm places, as they will deteriorate over time, even if kept in a cool place shelf life is 2-3years. And don't let them fully discharge too many times, if you are using rechargables, but don't keep them fully charged either as that decreases shelf life. They like to be kept at about 50% capacity

I've found my favorite batteries to be NIMH. They preform similarily to lithiums in the cold, but do not mind the warm temps and will last for years. They may be drained completely or just partially before recharged as well. There only problem is that they loose about 2% per day not even being used.

Dave,
I never have on the LRF, but I use the Duracell "Ultra" in it, the GPS, 35P, headlamps and anything else that hits cold weather or needs to last a long time. The voltage seems to stay higher on them and life is almost exactly twice as long. I also carry HALF as many spare batteries in my bag as a result!

Why they last longer, or the voltage stays high enough my GPS don't turn off is beyond me, but they work really well. This Lithium battery in my Nokia lasts about 5-7 days, gets left on 24/7 too. I've had this phone here since July, and it don't get plugged in unless it starts hollerin at me to charge it. Charges in less than an hour too!

MTBA,
Any idea why the Ultra's keep voltage higher and last longer, when in the same size package and both are alk's?

Interesting on the ultras, I have not tried them, just figured they would have been to close to regular Duracell's. Like you said they are the same size so how could they be much different.

Basically the only way they could make them run better in the cold is to reduce the resistence within the battery, like using more conductive materials on the electrodes, which they must have done. Also to get more life out of them they must have changed the construction to gain more usable internal volume although there really could not be too much of a gain from that.

I think that lowering the resistence must be the main change. Because of this I think they would work better for applications, like GPS, Flash Lights and Cameras. I bet that the regular Duracell's for use in things like TV remotes, and alarm clocks would actually last longer since they don't draw many amps.

Overall I bet The lithium batteries will really take off here in the next few years as they keep improving them, sounds like your phone is doing good.

It's a Garmin GPS III. Lasts about 8-9 HRS on Duracell's, and about 18-20 HRS on The Ultra's.

Problem I had was snomachining, they'd get cold with the GPS in your pocket and it would shut off and loose the track. Warm the batteries back up and they'd be alright, voltage meter just indicated it fell off too far to stay on is all.

With the Ultra's, it will drop down about half way on the voltage meter but maintain that level in the cold. Cursor moves ultra slow when the unit's real cold, but it don't shut down. The GPS has a battery timer on it too, so I know how long it takes to use up the batteries in it.

The last trip I went on, it was on from 6am to 12am when I replaced the batteries about 30 minutes from my house on the road back.

The lithium might be worth a try, I hear it's good for cold weather. I'm certainly impressed with this cell phone battery. When I was on a job out in the bush this summer, I charged the cell battery from the generater set they run everything on and I thought my battery was taking a dive on me. I'd get about 13-14 hrs of standby time on it and had to charge it evey night if I talked on it for 15-30 minutes.

It wasn't the battery, it was the gen set power source they tell me. I still have the new spare battery my wife sent me for it. Soon as I got home it was back to 5-7 days a week, 24/7 again... worked fine again.

I get 26 Everready Alkaline AA batteries (copper top) for $10 @ BJ's Warehouse, the local mass market place.
At that price I don't bother with rechargeables and don't mind chuckin' em out and replacing them whenever necessary. I like carring spares because I always keep at least one spare set inside my shirt pocket, under my coat, where they stay very warm should the sub-freezing temperatures get to the set in use.
Final note: I intentionally carry a GPS, a 2 way radio and flahlights that all use the same batteries. That way, in an emergency, I can always take the batteries from one and use them in the other.
It already happened once when I did not notice that the light was on in my Magellan and it quickly ate up the spare set of batteries. [img]images/icons/rolleyes.gif[/img]
I love hunting the big woods but I also love getting back to the camp at night.